Answers

Honestly here is my answer to this. Yes upgrading the ram as machead3 suggested would be the first and cheapest thing and honestly with that model upgrading the ram is super easy to do and doesn't require special tools. To the SSD- yes this would be beneficial but would you really need it if you do alot of programs or just need the overall speed of reads and writes SSD literally blow the doors off of any hard disk that was out in the time your macbook came out. i recommend the Samsung 830 series as it has low power consumption and at 256GB with for only 200 since you could use the adapter cable they include in the box i would go for the 20 dollar extra pack that way you have this but you cannot use Norton ghost as it is for windows only things you will need: a SSD of your choosing ( imho Samsung or ocz vertex maybe 3 since you have an older system without sata 3 ) a small Philips head screwdriver and a good finger to pry with the install is cake on this macbook. along with this i recommend using superduper to...

it seems to me like the logic board does need to be replaced and honestly wouldn't be too hard to get a hold of another one. on eBay i have seen the i7 4gb ram boards for 250-350 with warranty from sellers. honestly in my opinion you could do two things sell it whole as is for arounf 400-500 depending on model, mine was a core 2 duo 1.86 ghz with no ssd and a bad keyboard i got 425 for it as a reference for you. I was thinking you could replace the motherboard but what if one of your cables is bad in there aka the keyboard cable i would look in there and see if any of the liquid indicators are tripped on the battery ad did you take the motherboard out and clean the back side of it? i have succesfully repaird liquid damaged macbook airs before depending on severity. last one was a 2011 i repaired it used a heat gun on the motherboard and cutomer came back a week later and it wont boot not even with pram or sram

where they the exact same models? same year and everything? if so i don't see why that wouldn't work but you know how apple is with things make things hard to do. honestly it seems like its telling you the screen isn't correct for the family of laptop you have put the new screen into maybe it was a year newer or something but Im thinking there has to be a way to get that thing to bypass kernel panic with some coding.

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